DE60216965T2 - METHOD FOR CUTTING A POLY (VINYL ALCOHOL) MEMBER - Google Patents

Abstract

A process for cutting a poly (vinyl alcohol) (PVOH) member, which comprises cutting the member with a cutting edge, the cutting edge having a temperature of at least 100° C.

Description

The The present invention relates to a method of cutting a poly (vinyl alcohol) (PVOH) component, especially in the form of a Foil or a sheet, and on a cutting machine for cutting of foils or sheets made of PVOH.

synthetic Polymer materials, despite the increased cost of the raw materials needed for your Synthesis are still widely used in the manufacturing industry. The polymeric material can either be used to protect the to shape the goods to be produced or for their packaging.

Where it is necessary that the goods or the packaging in Dissolve water, either when the article has performed its function or at the content release the packaging, then it is advantageous if the used Material in addition for solubility is biodegradable. The main reason for the use of polymeric material for both of these uses is that, generally speaking, the properties tailored to a polymer to meet special requirements. For example, by use suitable starting materials and production conditions, the tensile strength, the elasticity, the density, the biodegradability, the solubility, the hydrophobic Properties etc. according to the proposed Application or the eventual End use changed become.

Typical is the material of choice in such situations PVOH, which is good solubility having. PVOH is also biodegradable, which makes it especially suitable makes to pass into the sewage treatment system.

exemplary for one Type of packaging is a matrix of wells that are in one Foil are formed from PVOH, wherein the wells are a solid or liquid Keep product. The wells are of suitable size, to pick up and retain the product. If the product added to the well a sealing sheet is placed over it and with the underlying one Sheet sealed. Individual bags are then made by Cutting the leaf.

US-A-4,405,536 describes methods of cutting with a heated component, a variety of hollow plastic membranes, consisting of thermoplastic Material, e.g. PVOH, and to seal the holes of the same. The membranes are in the form of a bundle.

The Difficulty in using PVOH as a polymeric sheet material is that PVOH is a relatively elastic at ambient temperatures and malleable polymer is what makes it difficult to cut. In known methods for cutting PVOH, a knife or a blade used at room temperature. To perform the cutting is a very sharp blade is required, which with a considerable degree must be created by force. The blade used must be sharpened frequently, which slows down production. Another possible solution to the problem of removal individual bags, namely just the perforation of the leaves to provide a line along which the consumer the individual Can tear out pockets, to get a single bag does not work. The tensile properties of PVOH make it difficult to stretch the sheet along the perforations to tear.

Because it is known that PVOH softens when exposed to heat, It has been thought that room temperature is the appropriate temperature for the blade is when used to cut PVOH. It is further known that excessive heat, when applied to PVOH whose solubility is reduced. This is a major disadvantage, if desired, of the water-soluble ones Maintain properties of PVOH. We now have a surprise found out that a knife or a blade that has a higher temperature has, can be used to cut PVOH, without the blade Contaminate with molten or burned PVOH and without the water solubility of the PVOH. We also surprisingly found out that such a heated knife or blade will make the PVOH better can cut as a non-heated knife or blade and further that the heated knife or blade requires less frequent sharpening as a non-heated one Knife or blade.

The The present invention is defined by claim 1 and provides a method of cutting a PVOH component, such as a sheet or foil containing it, the component to cut with a cutting edge, the cutting edge a Temperature from 110 to 160 ° C having.

• i) Aufheizen einer Schneidkante auf eine Temperatur von 110 bis 160°C, wobei die Schneidkante vorgegeben ist durch ein Paar von angewinkelten Seiten;
• ii) Ziehen von Material, d.h. das Bauteil, das zu schneiden ist, in die Nähe der Schneidkante;
• iii) Erfassen des Bauteils, z.B. in der Form einer Folie oder eines Blattes, mit der Schneidkante unter Verwendung genügend angewendeter Kraft, um das Bauteil zu schneiden; und
• iv) Bewegen des Materials und der Schneidkante relativ zueinander, um einen Schnitt zu bewirken,

wobei die zwei Seiten, welche die Schneidkante vorgeben, einen Winkel von weniger als 30° in Bezug aufeinander einnehmen.An embodiment of the present invention also provides a method of cutting a PVOH component, such as a PVOH sheet or film, the method comprising the steps of:

• i) heating a cutting edge to a temperature of 110 to 160 ° C, wherein the cutting edge is predetermined by a pair of angled sides;
• ii) drawing material, ie the component that belongs to is cut, near the cutting edge;
• iii) detecting the component, eg in the form of a foil or a sheet, with the cutting edge using sufficient applied force to cut the component; and
• iv) moving the material and the cutting edge relative to one another to effect a cut,

wherein the two sides which define the cutting edge occupy an angle of less than 30 ° with respect to each other.

• i) eine Produktladestation, in welcher Produkt in ein vorgeformtes Abteil aus einem ersten polymerischen Material geladen wird;
• ii) eine Abdichtstation, in welcher ein Blatt eines zweiten polymerischen Materials über das erste polymerische Material gelegt wird und mit diesem abgedichtet wird, um ein Laminat zu bilden, wobei entweder eines oder beide der ersten und zweiten polymerischen Materialien ein PVOH sind;
• iii) eine Schneidestation, die eine erhitzte Schneidkante hat, welche vorgegeben wird durch ein Paar von angewinkelten Seiten, um das laminierte Material zu erfassen und zu schneiden; und
• iv) eine Verpackungsstation, um das geschnittene Produkt zu verpacken,

wobei die Schneidkante auf eine Temperatur von 110 bis 160°C aufgeheizt wird und die zwei Seiten, welche die Schneidkanten vorgeben, einen Winkel von weniger als 30° in Bezug aufeinander aufspannen.The present invention additionally provides, in a method according to the invention as defined by claim 1, the use of a device for cutting leaves, the device comprising:

• i) a product loading station in which product is loaded into a preformed compartment of a first polymeric material;
• ii) a sealing station in which a sheet of second polymeric material is laid over and sealed to the first polymeric material to form a laminate, either or both of the first and second polymeric materials being a PVOH;
• iii) a cutting station having a heated cutting edge defined by a pair of angled sides to engage and cut the laminated material; and
• iv) a packaging station to package the cut product,

wherein the cutting edge is heated to a temperature of 110 to 160 ° C and the two sides, which define the cutting edges, an angle of less than 30 ° with respect to each other span.

The Temperature of the cutting edge is most preferably from 130 ° to 140 ° C. The precise temperature is not absolutely critical; the heated cutting edge can be easy at a temperature in a preset temperature range, e.g. within 5 ° C or 10 ° C from the desired temperature, being held.

It is common with a cutting edge, that it is given from two sides, which maintain a suitable angle to each other. Every angle can to be used with the present invention, although desirable is that the angle is less than 30 °, preferably from 12 to 18 °. A sharper edge makes it possible that thicker components like leaves can be cut more easily.

The Cutting edge can e.g. on a rotary knife, a non-rotating Knife, a rotary crusher or a folding rule or a die be arranged. The selection of the cutting edge, e.g. Knife, will depend on the specific configuration in which the material to cut is.

The Cutting edge can against a pedestal like an anvil or a Cutting the roll (as described below), which the component during the Cutting operation (a breaking operation) supports. The pedestal can be made from any suitable compliant material such as metal or rubber related surface be prepared. The cutting edge can be against an opposite stationary or movable edge work, which has no or no cutting edge in accordance may be with this invention (a scissors cutting operation).

In a feature of the invention, the cutting edge on a die be arranged. The die can be of any 2-dimensional shape such as a square, a rectangle, a circle or an oval, whereby it has the advantage of making more complex shapes out of the component can be cut out, such as curves and sharp (less than 90 °) angle. An additional one Advantage is that it is the requirement for a separate cutting edge avoids to get in each of the X and Y-axis of the component to be cut. Another feature is that the die may be connected to a vacuum source, thereby reducing it allows that the die will cut the cut piece after the cutting operation lifts off the component. In a further advantage, the die rotate about its vertical axis, further improving cutting efficiency of the die increased becomes.

Advantageous is the cutting edge along and substantially perpendicular to the circumference a roller arranged. Arranging the cutting edge along the Roller allows it the cutting edge to turn with the movement of the material, so that part of the cutting edge which engages the material at a higher Temperature is maintained. conventional the roller is in the form of a disc to allow it to that a field of rolls can be used to make a part, like a foil or a sheet, cut into more than one section. The use of a number of slices allows that instead of one whole roller individual discs can be replaced if it is required.

Advantageous the cutting edge is curved. The curvature preferably has a cross section with a radius of curvature of 0.3 to 0.7 mm, being approximately 0.5 mm are especially preferred. The curvature of the cutting edge extends the Service life of the cutting edge.

Any PVOH can be cut using the process of the present invention, although it is preferred that the PVOH be water-soluble. An example of Favor PVOH, which can build up the PVOH component, is ethoxylated PVOH. The PVOH may be partially or fully alcoholized or hydrolyzed. For example, it may be at least 40%, preferably from 70 to 92%, more preferably about 88% or 92%, alcoholized or hydrolyzed. It is known that the degree of hydrolysis affects the temperature at which the PVOH begins to dissolve in water.

88 % Hydrolysis corresponds to a PVOH solubility in cold (i.e., room temperature) Water while 92% hydrolysis corresponds to a PVOH which is soluble in warm water. A preferred PVOH that can be further processed, e.g. by Training in a foil or by casting, such as injection molding, is in the form of granules in the name of CP 1210T05 by the Soltec Developpement SA of Paris, France.

Advantageous For example, the PVOH may be substantially anhydrous, i. less than 4 wt .-% water, preferably less than 2 wt .-% water. We have found out that such PVOH, especially if it is in the In the form of a film when heated, e.g. during a thermoforming step, less of the shrinkage is exposed.

The PVOH component can have any shape. Desirable however, it is in the form of a sheet or foil. Generally, the sheet or film has a thickness of 40 to 300 microns, preferably from 80 to 200 μm, even more preferably from 100 to 150 μm and most preferably from 120 to 150 μm.

The PVOH component is not necessarily in the form of a sheet or a film before, it can be any thickness, shape or Have shape. The PVOH component may e.g. rigid or yielding be. The PVOH component may e.g. in the form of a three-dimensional Casting available. It can e.g. a thickness in the area of cutting have, by 15 microns to 30 mm, preferably from 30 μm to 25 mm, more preferably 80 μm up 20 mm. Preferably, however, the component is in the form of a film or a leaf in front.

The PVOH component is desirable in a form such that when sealed with foil, a water-soluble container is provided which contains at least one mixture. Consequently, can the PVOH component e.g. have the shape of a foil or a sheet, that has a bag in it. The bag can be made by a casting technique, e.g. by thermoforming, vacuum casting, injection molding or blow molding, getting produced.

If the component is integral with the film before being sealed together be present, and in the form of a single film, which with heat sealed to itself a horizontal or vertical mold fill seal process can be performed, around envelopes to provide a mixture containing. Pillow packets can out two different films are produced.

In a further embodiment the PVOH component may be in the form of a more rigid casting, e.g. manufactured by injection molding or blow molding. Such a mold may be in the form of an open container, which is filled with at least filled a mixture and then with at least one film by the method of This invention is sealed. Such containers are e.g. in WO 01/36290.

One injection-molded component forming a container has walls which generally have a thickness such that the container is rigid. For example can the outer walls and any interior walls independently a thickness of more than 100 μm, e.g. more than 150 μm or more than 200 μm, 300 μm, 400 μm, 500 μm, 750 μm or 1 mm. Typical is the thickness of 200 microns to 1000 microns, preferably of 300 μm up to 500 μm.

• a. Herstellung einer Tasche, umgeben von einem Abdichtungsteil in einer Folie;
• b. Befüllen der Tasche mit der Mischung;
• c. Platzieren einer Folie oberhalb der befüllten Tasche und über dem Abdichtungsteil;
• d. Abdichtung der Folien zusammen im Abdichtungsteil, z.B. durch Heißsiegeln.

The container may also be made of two sheets, one of the sheets being the water-soluble component. For example, a suitable process includes:

• a. Production of a bag, surrounded by a sealing part in a film;
• b. Filling the bag with the mixture;
• c. Placing a film over the filled bag and over the sealing member;
• d. Sealing the films together in the sealing part, eg by heat sealing.

The Thickness of for The film used to make the bag is preferably 40 to 300 μm, more preferably 80 to 200 μm, specifically 100 to 160 μm, more specifically 100 to 150 mm and most especially 120 to 150 μm.

The bag can be formed by, for example, vacuum forming or thermoforming. For example, in a thermoforming process, the film may be drawn or blown into a mold. Thus, the film is heated to the thermoforming temperature using a hot plate assembly and then pulled down under vacuum or blown down under pressure into the mold. One skilled in the art can select a suitable temperature, pressure or vacuum and residence time to achieve a suitable bag. The amount of vacuum or pressure used and the hot working temperature depend on the thickness and porosity of the film and the polymer or polymer blend used. Thermoforming of films is a well-known technique; Thermoforming of PVOH films is described, for example, in WO 00/55045.

After this the bag with the desired mixture filled is, a foil is above the filled bag and above the Sealing placed away, and the films are on the sealing part heat sealed together by the process of the present invention. The thickness of the sealing film is generally from 20 to 160 μm, preferably from 40 to 100 μm, as 40 to 80 microns or 75 to 95 μm.

In all the above embodiments can they individual container or groups of containers be separated using the cutting process of the present Invention.

The PVOH component, especially if it is in the form of a sheet or a Film is present, a single component or a laminated component be, e.g. the sheet or film as disclosed in GB-A-2,244,258. While a single slide pin holes may be two or more layers in one Laminate unlikely to have pinholes that match each other.

The Component, e.g. a sheet or a foil, can by any Process, e.g. by casting, such as injection molding, or Extrude, blow or by molding. The sheet or the foil can non-oriented, monoaxial oriented or biaxially oriented be. If the layers are oriented in the sheet or foil are, they usually have the same orientation, although their orientation levels are different could be, if desired.

The Layers in a laminate can the same or different. Consequently, they can all be the same PVOH polymer or different PVOH polymers or even a PVOH polymer and another polymer. Because the film is laminate and intended is, water-soluble To be, each of the layers should be water-soluble.

The Mixture (s) which are in the container or in each compartment of the container can be held can independently from each other a fiber care, a surface care or a detergent composition be.

consequently can they e.g. a dishwashing, water softening, laundry or detergent compositions or a rinse aid be. Such compositions can be suitable for use in a home washing machine. The compositions can also independent a disinfectant, an antibacterial or an antiseptic Composition or a refill composition for a Spray by pusher type be. Such compositions are generally in bulk from 5 to 100 g, especially from 15 to 40 g. For example can be a laundry composition weigh from 15 to 40 g. A dishwashing composition can be of 15 to 30 g, and a water softening composition can weigh from 15 to 40 g.

The Composition (s) can a solid be. For example, it may be a particulate or granulated solid or be a tablet. It can also be a liquid that thickened or gelled if desired. The fluid composition may be non-aqueous (i.e. dry) or aqueous, e.g. comprising less than 5% by weight of total or free water, be. A dry composition generally contains less than 1 Wt .-%, preferably less than 0.5 wt .-% water. The composition can have more than one phase. For example, it may be an aqueous composition and a liquid one Composition, which does not interfere with the aqueous Composition is miscible. It can also be a liquid composition and a separate solid state composition, e.g. in the shape of a ball, pill or speckles. The liquid composition may be thickened or gelled.

If the composition is an aqueous liquid which has a relatively high water content, e.g. above of 5% by weight of water, it may be necessary Be steps to make sure the liquid not the water solubility of the PVOH attacks, if it is in cold water or in water up to a Temperature of up to, for example, 35 ° C is soluble. Steps can be taken around the inner surface of the container to treat, e.g. by coating it with agents, see above such as PVdC (poly (vinylidene dichloride)) or PTFE (polytetrafluoroethylene), or to adjust the composition, to make sure it does not dissolve the PVOH. For example, it has been found making sure that the composition is high ionic Strength has or contains an agent, the loss of water through the walls of the container minimized, will prevent the composition from the PVOH of inside dissolve. This is in greater detail in EP-A-518,689 and WO 97 / 27,743.

The containers can have any desired shape. For example, the container may be an irregular or a regular geometric Have a shape, such as a cube, a cuboid, a pyramid, a dodecahedron or a cylinder. The cylinder may have any desired cross section, such as a circular, triangular or square cross section.

Referring now to the drawings and initially 1 , becomes a tailor 10 within a frame assembly 11 held a base plate 12 contains. Attached to the underside of the base plate 12 are a pair of slider pickups 13 for sliding and holding the tailor 10 in terms of the production line. In 1 is the production line only with respect to the machine mounting bars 14 shown, between which a pair of sliders 15 is arranged, which by the Gleiteraufnehmer 13 is detected.

A series of knife holders 16 and heated blades 17 is on a knife support unit 18 assembled. The knife holders are mounted so as to allow them to be moved both laterally and vertically. The vertical movement of the knife holder 16 is controlled by a pneumatic flow module 19 and takes place in principle between a film cutting position and a rest position. The lateral movement of the knife holder 16 is by a knife transverse pneumatic cylinder 20 controlled. The temperature of the blades 17 can be controlled by the person operating the device. The exact set temperature depends on the material to be cut. The heater for the blades 17 is provided by electric cartridge heaters. Once the required temperature has been determined, it will be programmed into the machine by the operator and subsequently automatically controlled by the machine within a preset limit of that temperature.

The knife holder 16 are provided in a linear relationship along the direction of movement A of the sheet of material. The number of knife holders 16 and consequently the number of blades 17 will be determined by the dimension of the machine, the dimension of the compartments and the number of cuts to be made in each pass of the blade 17 over the sheet.

An anvil 21 is provided to provide a surface against which the blades 17 squeeze when cutting a material. The anvil 21 extends over an area of the base plate 12 , where the range is of sufficient dimension to form a surface for each blade 17 provide. The anvil 21 itself can be adjusted up and down along a vertical line so that the anvil moves the material sheet towards the blade 17 can push to facilitate the achievement of a smooth cut.

If required, due to the nature of the product being packaged, the entire cutting assembly can 10 be enclosed within an airtight hood (not shown) to prevent contamination or deterioration of the sheet material or product prior to its packaging.

in the Operating bags in a first sheet of packaging material, made of PVOH formed. The product to be packaged is placed in the pockets thus formed. The first one moves sheet together with the product to a sealing station in which a second sheet, also made of PVOH, over the first sheet is laid. The second sheet is the first sheet sealed by adhesive pressure, which is used to seal to build. The seals are arranged so that the product is in one package is isolated from the product in another bag.

From the sealing station, the packaged product is further advanced into the cutting assembly, indicated in the direction indicated by A in 1 , The seals of the packaged product are above the anvils 21 arranged. The anvils 21 are raised until they contact the seals. The heated blades are lowered and traverse the length of the gaskets to cut the gaskets to make the individually packaged product. The packaged product is then conveyed to a packaging station and packaged in a suitable manner to supply the customer.

The 2a and 2 B show a cutting element in the form of a disk blade 30 that has a cutting edge 31 having. The two surfaces 32 . 33 the cutting edge 31 give an angle α.

The illustrated angle α is 15 °. Usually the disc blade 30 mounted so that it is freely rotatable about its major axis and can rotate during the cutting operation.

Further Examples of cutting elements (not shown), which a Include heated cutting edge, are as follows: First, can a non-rotating blade can be used. The cutting becomes then performed by either holding the blade in a static position and the polymer sheet is moved, or the sheet remains static, and the blade can over its surface to be pulled.

Second, the Stahlzollstock-like blade can be used. Such a blade will typically be used in a non-continuous manner by being lifted off the sheet, lowered, to cut the leaf and then lift it off the leaf. Then a repositioning of the blade with respect to the blade takes place to bring the blade over the next part of the blade to be cut.

When third, a rotary crusher can be used. A rotary crusher works as follows: The blade is attached to a first roller, wherein the roller pushed is forced to capture a second roller. The one to be cut Leaf is passed between the two rollers, which are in synchronous Turn way. While the sheet passes between the two rollers, cutting the blades on the first roll the sheet, the second roll as a base acts against which the blades can push.

The Heat usually gets to the blades by means of electric cartridge heaters fed. The temperature of the blade is in accordance with the present Invention between 110 ° C and 160 ° C.

Of the The process described can be used to either continuously or intermittently cut web material. In addition to Provide heated blades to make a lateral cut across the To perform leaf material, may be a further heated blade or a series of heated blades also be included to the sheet material in one direction of the To cut movement through the machine of the sheet of material.

The The web itself can be single-ply or have a laminate structure. The procedure and the device are especially suitable to leaves to cut, which have a thickness of 60 to 300 microns, although other thicknesses can also be recorded with a suitable blade.

The required blade angle (α in 2 ) would depend essentially on the thickness of the material to be cut. Generally, a thicker material would require a smaller value of α, ie a sharper blade. Typically, the angle α has a value of less than 30 °, although a value of 12 ° to 18 ° has been found to be particularly advantageous.

The Cutting edge can have a curved cross-section to have. curvatures with a radius of curvature from 0.3 to 0.7 mm have been found to be advantageous, wherein a value of about 0.5 mm is particularly advantageous. The curvature increases the length of time a blade can be used before it needs to be replaced, which is too obvious Cost savings for the user and to an increased Production leads.

It becomes natural understood that the invention is not limited to the specific, is limited to details described herein, which are merely intended as Example, and that various modifications and changes within the scope of the claims possible are.

Claims (12)

Method for cutting a PVOH component, which comprises cutting the component with a cutting edge, wherein the edge has a temperature of 110 to 160 ° C. Method according to claim 1, wherein the PVOH member is in the form of a sheet or a foil is present. Method according to claim 1, wherein the sheet or film has a thickness of 40 to 300 microns. Method according to any of the preceding claims, wherein the cutting edge is dictated by a pair of angled ones Sides that maintain an angle of less than 30 ° with respect to each other. Method according to any of the preceding claims for cutting a film or sheet of PVOH, wherein the Method comprises the steps of: i) heating the cutting edge to a temperature of 110 to 160 ° C, wherein the cutting edge predetermined is through a pair of angled sides; ii) pulling from material to be cut near the cutting edge; iii) Detecting the sheet or foil with the cutting edge using sufficiently exercised Force to cut the sheet or foil; and iv) Move of the material and the cutting edge relative to one another Cut to effect, with the two sides showing the cutting edge pretend to take an angle of less than 30 ° to each other. Method according to claim 4 or 5, wherein the angle between the two sides which the cutting edge pretend to be between 12 and 18 °. Method according to any of the preceding claims, wherein the cutting edge is along and substantially perpendicular to Circumference of a roller is arranged. Method according to any of the preceding claims, wherein the cutting edge is disposed on a rotating knife, a non-spinning Knife, a rotary crusher or on a steel yardstick or a die. Method according to any of the preceding claims, wherein the cutting edge is curved is. Method according to any of the preceding claims, wherein the PVOH is water-soluble. Method according to claim 10, wherein the temperature of the cutting edge is not sufficient to the solubility properties of the PVOH. Use in a method according to any of the preceding claims of the device for cutting leaves, the device contains: i) a product loading station in which a product is preformed Compartment is loaded from a first polymeric material; ii) a sealing station in which a sheet of a second material the first polymeric material is considered and with this is sealed to form a laminate, either one or both of the first and second polymeric materials PVOH is, or are; iii) a cutting station having a heated cutting edge indicated by a pair of angled sides to grasp and cut the laminated material; and iv) a packing station to package the cut product, in which heated the cutting edge to a temperature of 110 to 160 ° C. and the two sides which define the cutting edge, one Angle of less than 30 ° in Relate to each other.